Opposition to a republic in Australia has risen to its highest level since 1999, a poll has found, as the Prince of Wales comes to the end of his tour of the country.

A total of 41% of 1,639 people asked over four days in April said they would be against scrapping the monarchy and becoming a republic, according to a survey conducted on behalf of The Australian newspaper.

This compares to 34% 19 years ago and 38% in August 2017.

One in two Australians (50%) backs the push for a republic, while 9% are uncommitted, according to the Newspoll survey conducted on behalf of the paper.

Charles’s tour of Australia, which ends on Tuesday, came as the future of the monarchy in the country remained unclear.

In 1999 a referendum was held over whether the Queen and Governor-General should be replaced with a president, with 54.87% voting against and 45.13% in favour.

The issue has continued to be a topic of debate ever since.

Just days before the prince arrived in Brisbane for his first official engagement, former prime minister Paul Keating claimed Charles would support Australia cutting ties with the monarchy and becoming a republic.

Mr Keating told the Sunday Times: “I have no doubt he believes Australia should be free of the British monarchy and that it should make its own way in the world.”

But he added: “None of that is to diminish the commitment and sense of duty that Prince Charles displays towards Great Britain and, as constitutional arrangements stand, towards Australia.

“He is a great friend of Australia — there is no doubt about that.”

Another former prime minister, Julia Gillard, told BBC Radio 4’s Today programme she believed at some point the country would become a republic.

Current PM Malcolm Turnbull has also previously spoken about the possibility of giving Australians their say on whether to scrap the monarchy after the Queen dies.

Throughout Charles’s week-long visit to Australia, crowds of people have turned out to catch a glimpse of the heir of the throne.

On Tuesday, Charles laid a wreath at Darwin Cenotaph before visiting the base of NORFORCE (North-West Mobile Force), an infantry regiment of the Australian Army Reserve.

There he spoke to soldiers who worked with Prince Harry at the regiment during his four-week secondment with the Australian military in 2015.

He will go on to visit the National Critical Care and Trauma Response Centre, set up after the 2002 Bali bombings, before flying home from Darwin on Tuesday evening.